1. Field of the Invention
The present invention relates generally to a system for mechanically and biologically decomposing garbage. More particularly, the present invention relates to a system for mechanically and biologically decomposing garbage such as kitchen waste material from a house, a restaurant or the like and industrial waste material from a foodstuff industry, an animal feed industry or the like.
2. Field of the Invention
Among various methods for disposing a foodstuff waste material, a widely employed method is to bury the waste material in the ground and another widely employed method is to dispose of the waste material by incinerating it. In this country, generally, garbage discharged from each house is disposed of by self-governing body and a foodstuff waste material from a foodstuff industry is disposed of as industrial waste material by an operator specializing in dealing with waste materials. However, the current status is that most of operators specializing in dealing with industrial waste materials utilize disposing facilities which are built and owned by the self-governing body. This means that they are merely a transporter, who transports the industrial waste materials to a certain burying location or an incinerator owned by the selfgoverning body. In the past, pig breeders collected foodstuff waste materials as fodder. In recent years, things changed due to not only a shortage in manpower but also a low price of pig meat in a meat market, causing the pig breeder to employ an artificial composite fodder for breeding pigs. This leads to the result that all the foodstuff waste materials are currently disposed by employing the burying method or the incinerating method.
As described above, the method of disposing foodstuff waste materials is divided into two types, i.e., the burying method and the incinerating method. However, each of the methods becomes a source of significant industrial public pollution in modern society.
(1) In practice, the burying method is accomplished by burying waste materials in a burying site peripheral to a sea or a burying site in a mountain or valley. Alternatively, the waste materials are buried in a location sufficiently deep below the ground surface. However, each of the aforementioned cases leads to a destruction of the natural environment. In view of the current status wherein worldwide attention has been paid to protection of the natural environmental from destruction, it is believed that a measure to be taken against pollution of a sea, river and others should seriously be considered and discussed as a significant problem to be solved in the near future. PA1 (2) On the other hand, the most significant problems inherent to the incinerating method are that an incinerator is manufactured at a expensive cost and it becomes increasingly difficult to obtain a previous agreement and approval from people living in the proximity of an incinerator to be installed. PA1 (3) Next, with respect to disposition of a garbage discharged from each house, self-governing bodies have taken positive actions since about ten years ago for allowing the garbage from each house to be disposed by each house itself as far as possible because of a limited capacity of disposing of the garbage in an incinerator owned by each self-governing body. PA1 (1) To practice the method, a certain quantity of soil is absolutely necessary. PA1 (2) Unpleasant odor is increasingly generated from the container day by day. PA1 (3) Noxious worms and insects such as grubs, flies or the like are born and grown in the container. PA1 (4) Although kitchen garbage can biologically be decomposed in the container naturally, it is unavoidable that so-called overflow occurs as a certain quantity of garbage is put in the container day by day. PA1 (5) The container is employed based on a fundamental condition that the finally disposed material is utilized as a fertilizer. If no farm is available for an user, the resultant material can not practically be used as a fertilizer irrespective of some available quantity of soil for biological decomposition of the garbage. PA1 (6) To provide the container for each user at an inexpensive cost, it is molded of plastic resin while having a very thin wall. For this reason, the container is readily damaged or broken by a small magnitude of force imparted thereto from the outside. PA1 (7) The container which has been employed at present is molded of plastic resin having less resistance to the elements. Thus, the container is naturally damaged or broken as time elapses. PA1 (8) Dogs or cats often bring the decomposing garbage away from the container to the outside. This induces a so-called scattering pollution. PA1 (1) With respect to method of decomposing garbage in the water within a short period of time, an apparatus for carrying out this method is manufactured at an expensive cost. For this reason, the present invention is based on the same principle as the conventional principle of burying garbage in the ground in accordance with. To carry out the present invention, pulverized wood is employed instead of soil. Prior to practical use, the pulverized wood is thermally processed at a temperature of 130 .degree. C. for the purpose of removing various noxious substances in the pulverized wood and sterilizing the same. This step of previous processing is intended to promote growth of garbage decomposing bacilli, elevate the temperature of growing the garbage decomposing bacilli and to remove from the garbage decomposing vessel a lignin acid which is effective for preventing sprouts from growing. Consequently, the resultant products derived from the system of the present invention can be utilized as a fertilizer having improved safety. PA1 (2) Generating of odor during natural decomposition of the garbage is attributable to various kinds of bad-smelling gases generated during natural decomposition of the garbage. According to the present invention, the problem concerning generation of the odor has been solved by using aerobic bacilli in the garbage decomposing vessel for biological decomposition to improve the capability of decomposition of the garbage and moreover employing very finely pulverized wood to form garbage decomposing bacillus growing bed having a excellent air permeability and porosity. Compressed air may be blown in the garbage decomposing vessel, as required. PA1 (3) It has been hitherto considered that it is practically impossible to prevent noxious worms and insects from being born and grown during a step of decomposition of organic materials. In other words, decomposition of the organic materials has been heretofore unavoidably accompanied by generation of specific unpleasant odor. However, according to the present invention, arrangement of the system as described in the preceding paragraph (2) has eliminated the problem concerning birth and growth of noxious insects and worms in the garbage decomposing vessel. PA1 (4) To promote decomposition of an organic garbage, the system of the present invention may be utilized such that the garbage is introduced into the interior of the system as it is left in the original state thereof. However, it is effective from the viewpoint of designing and constructing the system in smaller dimensions that the garbage is disintegrated into a large number of pieces by a disposer to enlarge an effective exposure surface area of the garbage. If garbage is introduced directly into the interior of the garbage decomposing vessel together with water required by the disposer, there arises a problem that a long time is taken until the garbage is completely decomposed, because the garbage is washed with water each time the garbage is introduced into the garbage decomposing vessel. PA1 (5) According to the present invention, garbage is biologically decomposed in accordance with nature while water is separated from the disintegrated garbage. In addition, pulverized wood is employed for forming garbage decomposing bacillus growing bed instead of soil after it is previously processed at an elevated temperature for removing various noxious matters therefrom. Thus, the resultant product derived from biological decomposition in the garbage decomposing vessel after a certain period of time elapses can be utilized as an organic fertilizer. This means that the system of the present invention matches well with the recent tendency for an agricultural process to be practiced using an organic fertilizer. PA1 (6) The disposer is arranged by the sink of a kitchen in a house or the sink of a restaurant. As garbage is put in the disposer by an user, the disintegrated garbage is conveyed to the solid/liquid separator together with water so that the dewatered disintegrated garbage is forcibly introduced into the interior of the garbage decomposing vessel while the separated water is drained to the outside. The dewatered disintegrated garbage is stirred together with the pulverized wood and the garbage decomposing bacilli in the garbage decomposing vessel in operative association with the disposer. On completion of the stirring operation, the garbage decomposing vessel is automatically brought to an inoperative state. Therefore, a significant feature of the present invention consists in that no manpower is required at all.
The most significant problems inherent to the burying method are that noxious insects are born and grown in the burying site and unpleasant odor is generated from the burying site, whereby people living in the proximity of the burying site unavoidably suffer from the noxious insects and the unpleasant odor. It is believed that this problem is derived from a limited narrow area or space which is generally available in this country for practicing the burying method as well as a limited quantity of waste materials to be buried per unit area.
Garbage to be disposed by employing the incinerating method functions like water. In other words, disposition of the garbage is similar to vaporizing water by burning heavy oil. Accordingly, burying of the garbage with oil leads to a significant loss of energy which in turn causes a loss for human beings. In addition, it becomes increasingly unacceptable from the viewpoint of protection of the natural environment and the human beings from destruction or injury to employ the burying method for disposing of garbage, since carbon dioxide gas is generated during an incinerating operation and various noxious matters are simultaneously scattered in the air.
Specifically, each self-governing body has recommended employment of a bottomless container molded of plastic resin for the purpose of biologically decomposing kitchen garbage naturally. The container is practically used such that the garbage is put in the bottomless container mounted directly on the ground and a cover is then placed on the container so that the garbage is biologically decomposed in the presence of soil as time elapses. However, it has been found that the conventional method which has been positively recommended by self-governing bodies until now to use the bottomless container in the above-described manner has the following drawbacks.
At present, the method recommended by self-governing bodies is mostly employed by individual houses located in the suburbs. Therefore, each self-governing body does not suffer directly from problems associated with decomposition of kitchen garbage but each house in a city, town or the like suffers from these problems.
To obviate the above problems, it has been proposed to use an apparatus for storing a garbage in a refrigerated state or an electronic range type incinerator for the purpose of disposing of garbage. However, it is obvious that the foregoing proposal is not a complete resolution of the problems.